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Human infancy is marked by fastest postnatal brain structural changes. It also coincides with the onset of many neurodevelopmental disorders. Atlas-based automated structure labeling has been widely used for analyzing various neuroimaging data. However, the relatively large and nonlinear neuroanatomical differences between infant and adult brains can lead to significant offsets of the labeled structures in infant brains when adult brain atlas is used. Age-specific 1- and 2-year-old brain atlases covering all major gray and white matter (GM and WM) structures with diffusion tensor imaging (DTI) and structural MRI are critical for precision medicine for infant population yet have not been established. In this study, high-quality DTI and structural MRI data were obtained from 50 healthy children to build up three-dimensional age-specific 1- and 2-year-old brain templates and atlases. Age-specific templates include a single-subject template as well as two population-averaged templates from linear and nonlinear transformation, respectively. Each age-specific atlas consists of 124 comprehensively labeled major GM and WM structures, including 52 cerebral cortical, 10 deep GM, 40 WM, and 22 brainstem and cerebellar structures. When combined with appropriate registration methods, the established atlases can be used for highly accurate automatic labeling of any given infant brain MRI. We demonstrated that one can automatically and effectively delineate deep WM microstructural development from 3 to 38 months by using these age-specific atlases. These established 1- and 2-year-old infant brain DTI atlases can advance our understanding of typical brain development and serve as clinical anatomical references for brain disorders during infancy.
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Atlas como Assunto , Encéfalo , Imagem de Tensor de Difusão , Substância Cinzenta , Substância Branca , Humanos , Lactente , Pré-Escolar , Masculino , Substância Branca/diagnóstico por imagem , Substância Branca/anatomia & histologia , Substância Branca/crescimento & desenvolvimento , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/crescimento & desenvolvimento , Substância Cinzenta/anatomia & histologia , Imagem de Tensor de Difusão/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Encéfalo/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodosRESUMO
Preterm birth is associated with increased risk for a spectrum of neurodevelopmental disabilities. The cerebellum is implicated in a wide range of cognitive functions extending beyond sensorimotor control and plays an increasingly recognized role in brain development. Morphometric studies based on volume analyses have revealed impaired cerebellar development in preterm infants. However, the structural covariance between the cerebellum and cerebral cortex has not been studied during the neonatal period, and the extent to which structural covariance is affected by preterm birth remains unknown. In this study, using the structural MR images of 52 preterm infants scanned at term-equivalent age and 312 full-term controls from the Developing Human Connectome Project, we compared volumetric growth, local cerebellum shape development and cerebello-cerebral structural covariance between the two groups. We found that although there was no significant difference in the overall volume measurements between preterm and full-term infants, the shape measurements were different. Compared with the control infants, preterm infants had significantly larger thickness in the vermis and lower thickness in the lateral portions of the bilateral cerebral hemispheres. The structural covariance between the cerebellum and frontal and parietal lobes was significantly greater in preterm infants than in full-term controls. The findings in this study suggested that cerebellar development and cerebello-cerebral structural covariance may be affected by premature birth.
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Material reinforcement commonly exists in a contradiction between strength and toughness enhancement. Herein, a reinforced strategy through self-assembly is proposed for alginate fibers. Sodium alginate (SA) microstructures with regulated secondary structures are assembled in acidic and ethanol as reinforcing units for alginate fibers. Acidity increases the flexibility of the helix and contributes to enhanced extendibility. Ethanol is responsible for formation of a stiff ß-sheet, which enhances the modulus and strength. The structurally engineered SA assembly exhibits robust mechanical compatibility, and thus reinforced alginate fibers possess an improved tensile strength of 2.1 times, a prolonged elongation of 1.5 times, and an enhanced toughness of 3.0 times compared with SA fibers without reinforcement. The reinforcement through self-assembly provides an understanding of strengthening and toughening mechanism based on secondary structures. Due to a similar modulus with bones, reinforced alginate fibers exhibit good efficacy in accelerating bone regeneration in vivo.
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Alginatos , Regeneração Óssea , Resistência à Tração , Alginatos/química , Regeneração Óssea/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Ácido Glucurônico/química , Teste de Materiais , Ácidos Hexurônicos/química , Alicerces Teciduais/químicaRESUMO
Numerous studies utilizing magnetic resonance imaging (MRI) have observed sex and interhemispheric disparities in sulcal morphology, which could potentially underpin certain functional disparities in the human brain. Most of the existing research examines the precentral sulcus comprehensively, with a rare focus on its subsections. To explore the morphology, asymmetry, and sex disparities within the inferior precentral sulcus (IPCS), we acquired 3.0T magnetic resonance images from 92 right-handed Chinese adolescents. Brainvisa was used to reconstruct the IPCS structure and calculate its mean depth (MD). Based on the morphological patterns of IPCS, it was categorized into five distinct types. Additionally, we analyzed four different types of spatial relationships between IPCS and inferior frontal sulcus (IFS). There was a statistically significant sex disparity in the MD of IPCS, primarily observed in the right hemisphere. Females exhibited significantly greater asymmetry in the MD of IPCS compared to males. No statistically significant sex or hemispheric variations were identified in sulcal patterns. Our findings expand the comprehension of inconsistencies in sulcal structure, while also delivering an anatomical foundation for the study of related regions' function.
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Preterm (PT) birth is a potential factor for abnormal brain development. Although various alterations of cortical structure and functional connectivity in preterm infants have been reported, the underlying microstructural foundation is still undetected thoroughly in PT infants relative to full-term (FT) neonates. To detect the very early cortical microstructural alteration noninvasively with advanced neurite orientation dispersion and density imaging (NODDI) on a whole-brain basis, we used multi-shell diffusion MRI of healthy newborns selected from the Developing Human Connectome Project. 73 PT infants and 69 FT neonates scanned at term-equivalent age were included in this study. By extracting the core voxels of gray matter (GM) using GM-based spatial statistics (GBSS), we found that comparing to FT neonates, infants born preterm showed extensive lower neurite density in both primary and higher-order association cortices (FWE corrected, P < 0.025). Higher orientation dispersion was only found in very preterm subgroup in the orbitofrontal cortex, fronto-insular cortex, entorhinal cortex, a portion of posterior cingular gyrus, and medial parieto-occipital cortex. This study provided new insights into exploring structural MR for functional and behavioral variations in preterm population, and these findings may have marked clinical importance, particularly in the guidance of ameliorating the development of premature brain.
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Imagem de Tensor de Difusão , Recém-Nascido Prematuro , Lactente , Humanos , Recém-Nascido , Encéfalo , Substância Cinzenta/diagnóstico por imagem , Córtex EntorrinalRESUMO
Dormancy is an adaptive trait which prevents seeds from germinating under unfavorable environmental conditions. Seeds with weak dormancy undergo pre-harvest sprouting (PHS) which decreases grain yield and quality. Understanding the genetic mechanisms that regulate seed dormancy and resistance to PHS is crucial for ensuring global food security. In this study, we illustrated the function and molecular mechanism of TaSRO1 in the regulation of seed dormancy and PHS resistance by suppressing TaVP1. The tasro1 mutants exhibited strong seed dormancy and enhanced resistance to PHS, whereas the mutants of tavp1 displayed weak dormancy. Genetic evidence has shown that TaVP1 is epistatic to TaSRO1. Biochemical evidence has shown that TaSRO1 interacts with TaVP1 and represses the transcriptional activation of the PHS resistance genes TaPHS1 and TaSdr. Furthermore, TaSRO1 undermines the synergistic activation of TaVP1 and TaABI5 in PHS resistance genes. Finally, we highlight the great potential of tasro1 alleles for breeding elite wheat cultivars that are resistant to PHS.
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Dormência de Plantas , Triticum , Dormência de Plantas/genética , Triticum/genética , Germinação/genética , Melhoramento Vegetal , FenótipoRESUMO
Deep sowing is a traditional method for drought resistance in maize production, and mesocotyl elongation is strongly associated with the ability of maize to germinate from deep soil. However, little is known about the functional genes and mechanisms regulating maize mesocotyl elongation. In the present study, we identified a plant-specific SIMILAR TO RCD-ONE (SRO) protein family member, ZmSRO1e, involved in maize mesocotyl elongation. The expression of ZmSRO1e is strongly inhibited upon transfer from dark to white light. The loss-of-function zmsro1e mutant exhibited a dramatically shorter mesocotyl than the wild-type in both constant light and darkness, while overexpression of ZmSRO1e significantly promoted mesocotyl elongation, indicating that ZmSRO1e positively regulates mesocotyl elongation. We showed that ZmSRO1e physically interacted with ZmbZIP61, an ortholog of Arabidopsis ELONGATED HYPOCOTYL 5 (HY5) and showed a function similar to that of HY5 in regulating photomorphogenesis. We found that ZmSRO1e repressed the transcriptional activity of ZmbZIP61 toward target genes involved in the regulation of cell expansion, such as ZmEXPB4 and ZmEXPB6, by interfering with the binding of ZmbZIP61 to the promoters of target genes. Our results provide a new understanding of the mechanism by which SRO regulates photomorphogenesis and highlight its potential application in deep sowing-resistant breeding.
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Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Zea mays , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genéticaRESUMO
Ferroptosis provides an innovative theoretical basis and method for tumor therapy but is limited by the low efficiency of conventional iron delivery systems. Herein, an efficient supramolecular iron delivery system (SIDS) is demonstrated upon the hydrolysis of FeCl3, condensation of amino acids, and self-assembly of iron-containing components. The as-assembled SIDS possesses a shuttle-like core/shell structure with ß-FeOOH as the core and Fe3+/polyamino acid coordinated networks as shells. The iron content of SIDS is up to 42 wt %, which is greatly higher than that of ferritin. The iron-containing protein-mimic structure and shuttle-like morphology of SIDS facilitate tumor accumulation and cell internalization. Once exposed to the tumor microenvironment with overexpressed glutathione (GSH), the SIDS will disassemble, accompanied by the depletion of GSH and the release of Fe2+, leading to dual amplified ferroptosis. Primary studies indicate that SIDS exhibits outstanding antitumor efficacy on bladder cancer.
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Ferroptose , Ferro , Ferro/química , Ferritinas , Linhagem Celular TumoralRESUMO
The fat mass and obesity associated (FTO) locus consistently associates with higher body mass index (BMI) across diverse ancestral groups. However, previous small studies of people of Polynesian ancestries have failed to replicate the association. In this study, we used Bayesian meta-analysis to test rs9939609, the most replicated FTO variant, for association with BMI with a large sample (n = 6095) of Aotearoa New Zealanders of Polynesian (Maori and Pacific) ancestry and of Samoan people living in the Independent State of Samoa and in American Samoa. We did not observe statistically significant association within each separate Polynesian subgroup. Bayesian meta-analysis of the Aotearoa New Zealand Polynesian and Samoan samples resulted in a posterior mean effect size estimate of +0.21 kg/m2, with a 95% credible interval [+0.03 kg/m2, +0.39 kg/m2]. While the Bayes Factor (BF) of 0.77 weakly favors the null, the BF = 1.4 Bayesian support interval is [+0.04, +0.20]. These results suggest that rs9939609 in FTO may have a similar effect on mean BMI in people of Polynesian ancestries as previously observed in other ancestral groups.
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Índice de Massa Corporal , Povo Maori , População das Ilhas do Pacífico , Humanos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Teorema de Bayes , Predisposição Genética para Doença , Povo Maori/genética , Nova Zelândia , População das Ilhas do Pacífico/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Resumption of the increase in atmospheric methane (CH4 ) concentrations since 2007 is of global concern and may partly have resulted from emissions from rice cultivation. Estimates of CH4 emissions from rice fields and abatement potential are essential to assess the contribution of improved rice management in achieving the targets of the Global Methane Pledge agreed upon by over 100 countries at COP26. However, the contribution of CH4 emissions from rice fields to the resumed CH4 growth and the global abatement potential remains unclear. In this study, we estimated the global CH4 emissions from rice fields to be 27 ± 6 Tg CH4 year-1 in the recent decade (2008-2017) based on the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories. The trend of CH4 emissions from rice cultivation showed an increase followed by no significant change and then, a stabilization over 1990-2020. Consequently, the contribution of CH4 emissions from rice fields to the renewed increase in atmospheric CH4 concentrations since 2007 was minor. We summarized the existing low-cost measures and showed that improved water and straw management could reduce one-third of global CH4 emissions from rice fields. Straw returned as biochar could reduce CH4 emissions by 12 Tg CH4 year-1 , equivalent to 10% of the total reduction of all anthropogenic emissions. We conclude that other sectors than rice cultivation must have contributed to the renewed increase in atmospheric CH4 concentrations, and that optimizing multiple mitigation measures in rice fields could contribute significantly to the abatement goal outlined in the Global Methane Pledge.
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Gases de Efeito Estufa , Oryza , Agricultura/métodos , Solo , Metano/análiseRESUMO
Despite the increasing impact of atmospheric nitrogen (N) deposition on terrestrial greenhouse gas (GHG) budget, through driving both the net atmospheric CO2 exchange and the emission or uptake of non-CO2 GHGs (CH4 and N2 O), few studies have assessed the climatic impact of forests and grasslands under N deposition globally based on different bottom-up approaches. Here, we quantify the effects of N deposition on biomass C increment, soil organic C (SOC), CH4 and N2 O fluxes and, ultimately, the net ecosystem GHG balance of forests and grasslands using a global comprehensive dataset. We showed that N addition significantly increased plant C uptake (net primary production) in forests and grasslands, to a larger extent for the aboveground C (aboveground net primary production), whereas it only caused a small or insignificant enhancement of SOC pool in both upland systems. Nitrogen addition had no significant effect on soil heterotrophic respiration (RH ) in both forests and grasslands, while a significant N-induced increase in soil CO2 fluxes (RS , soil respiration) was observed in grasslands. Nitrogen addition significantly stimulated soil N2 O fluxes in forests (76%), to a larger extent in grasslands (87%), but showed a consistent trend to decrease soil uptake of CH4 , suggesting a declined sink capacity of forests and grasslands for atmospheric CH4 under N enrichment. Overall, the net GHG balance estimated by the net ecosystem production-based method (forest, 1.28 Pg CO2 -eq year-1 vs. grassland, 0.58 Pg CO2 -eq year-1 ) was greater than those estimated using the SOC-based method (forest, 0.32 Pg CO2 -eq year-1 vs. grassland, 0.18 Pg CO2 -eq year-1 ) caused by N addition. Our findings revealed that the enhanced soil C sequestration by N addition in global forests and grasslands could be only marginally offset (1.5%-4.8%) by the combined effects of its stimulation of N2 O emissions together with the reduced soil uptake of CH4 .
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Gases de Efeito Estufa , Ecossistema , Pradaria , Dióxido de Carbono/análise , Metano/análise , Óxido Nitroso/análise , Florestas , Solo , NitrogênioRESUMO
BACKGROUND: In neuroscience, accurately quantifying individual brain regions in large cohorts is a challenge. Differences in intracranial structures can suggest functional differences, but they also reflect the effects of other factors. However, there is currently no standardized method for the correction of intracranial structure measurements. PURPOSE: To identify the optimal method to counteract the influence of total intracranial volume (TIV) and gender on the measurement of intracranial structures. STUDY TYPE: Prospective. POPULATION/SUBJECTS: One hundred forty-one healthy adult volunteers (70 male, mean age 21.8 ± 1.7 years). FIELD STRENGTH/SEQUENCE: T1-weighted 3D gradient-echo sequence at 3.0 T. ASSESSMENT: A radiologist with 5 years of work experience screened the raw images to exclude poor-quality images. Freesurfer then performed automated segmentation to obtain measurements of intracranial structures. Male-only, female-only, and TIV-matched sub-samples were created separately. Comparisons between the original data and these sub-samples were used to assess the effects of gender and TIV. Comparison the consistency between TIV-matched sample and corrected data that corrected by four methods: Proportion method, power-corrected proportion method, covariate regression method, and residual method. STATISTICAL TESTS: Cohen's d for examining group distribution disparities, t-tests for probing mean differences, correlation coefficients to assess the relationships between intracranial substructure measurements and TIV. Multiple comparison corrections were applied to the results. RESULTS: The correlation coefficients between TIV and the volumes of intracranial structures ranged from 0.033 to 0.883, with an average of 0.467. Thirty significant volume differences were found among 36 structures in the original sample, while no differences were observed in the TIV-matched sample. Among the four correction methods, the residual method had highest consistency (similarity 94.4%) with the TIV-matched group. DATA CONCLUSION: The variation in intracranial structure sizes between genders was largely attributable to TIV. The residual method offers a more accurate and effective approach for correcting the effects of TIV on intracranial structures. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.
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The morphological development of the fetal striatum during the second trimester has remained poorly described. We manually segmented the striatum using 7.0-T MR images of the fetal specimens ranging from 14 to 22 gestational weeks. The global development of the striatum was evaluated by volume measurement. The absolute volume (Vabs) of the caudate nucleus (CN) increased linearly with gestational age, while the relative volume (Vrel) showed a quadratic growth. Both Vabs and Vrel of putamen increased linearly. Through shape analysis, the changes of local structure in developing striatum were specifically demonstrated. Except for the CN tail, the lateral and medial parts of the CN grew faster than the middle regions, with a clear rostral-caudal growth gradient as well as a distinct "outside-in" growth gradient. For putamen, the dorsal and ventral regions grew obviously faster than the other regions, with a dorsal-ventral bidirectional developmental pattern. The right CN was larger than the left, whereas there was no significant hemispheric asymmetry in the putamen. By establishing the developmental trajectories, spatial heterochrony, and hemispheric dimorphism of human fetal striatum, these data bring new insight into the fetal striatum development and provide detailed anatomical references for future striatal studies.
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Núcleo Caudado , Corpo Estriado , Gravidez , Feminino , Humanos , Segundo Trimestre da Gravidez , Corpo Estriado/diagnóstico por imagem , Núcleo Caudado/diagnóstico por imagem , Putamen/diagnóstico por imagem , Caracteres SexuaisRESUMO
PURPOSE: The objective of this research was to analyze and correlate the length of the left main coronary artery (LMCA) with significant clinical parameters using multi-slice CT (MSCT). MATERIALS AND METHODS: 1500 patients (851 males and 649 females; mean age 57.38 ± 11.03 [SD]; age range: 5-85 years) who underwent MSCT scans from September 2020 to March 2022 were retrospectively included. The data were applied to generate three-dimensional (3D) simulations of a coronary tree using the syngo.via post-processing workstation. The reconstructed images were then interpreted, and the collected data were subjected to statistical analysis. RESULTS: The results showed 1206 (80.4%) cases with medium LMCA, 133 (8.9%) with long LMCA, and 161 (10.7%) with short LMCA. The average diameter of LMCA at its midpoint was 4.69 ± 0.74 mm. The most frequent type of division of LMCA was bifurcation in 1076 (71.7%) cases; in 424 (28.3%) cases, the LMCA was divided into three or more branches. The dominance was right in 1339 (89.3%), left in 78 (5.2%), and co-dominant in 83 (5.5%) cases. There was a positive correlation between the length and branching patterns of LMCA, χ2 = 113.993, P = 0.000 (< 0.05). Other variables like age, sex, diameter of LMCA, and coronary dominance did not show any significant correlation. CONCLUSION: This study has demonstrated a significant association between the length and the branching pattern of LMCA, which may be essential in diagnosing and treating coronary artery patients.
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Vasos Coronários , Coração , Masculino , Feminino , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Vasos Coronários/diagnóstico por imagem , Angiografia Coronária/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: The objectives of this study were to evaluate the various branching patterns of segmental bronchi in the right middle lobe (RML) and to survey the anatomical diversity and sex-related differences of these branches in a large sample of the study population. MATERIALS AND METHODS: In this retrospective board-approved study with informed consent, 10,000 participants (5428 males and 4,572 females, mean age 50 ± 13.5 years [SD]; age range: 3-91 years) who underwent multi-slice CT (MSCT) scans from September 2019 to December 2021 were retrospectively included. The data were applied to generate three-dimensional (3D) and virtual bronchoscopy (VB) simulations of a bronchial tree using the syngo.via post-processing workstation. The reconstructed images were then interpreted to locate and classify distinct bronchial patterns in the RML. Cross-tabulation analysis and the Pearson chi-square test were used to calculate the constituent ratios of bronchial branch types and determine their significance between male and female groups. RESULTS: Our results revealed that the segmental bronchial ramifications of the RML were classified into two types mainly, i.e., bifurcation (B4, B5, 91.42%) and trifurcation (B4, B5, B*, 8.58%). There were no significant sex-related differences in the proportion of bronchial branches in the RML (P > 0.05). CONCLUSION: The current study has confirmed the presence of segmental bronchial variations in the RML lobe using 3D reconstruction and virtual bronchoscopy. These findings may have significant implications for the diagnosis of symptomatic patients and for carrying out specific procedures like bronchoscopy, endotracheal intubation, and lung resection.
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Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Masculino , Feminino , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Imageamento Tridimensional/métodos , Brônquios/diagnóstico por imagem , Pulmão , Broncoscopia/métodosRESUMO
PURPOSE: The objectives of this study were to evaluate various branching patterns of segmental bronchi in the left superior and lingular lobes and to survey the anatomical diversity and sex-related differences of these branches in a large sample of the study population. MATERIALS AND METHODS: Overall, 10,000 participants (5428 males, and 4572 females, mean age 50 ± 13.5 years [SD] years; age range: 3-91 years) who underwent multi-slice CT (MSCT) scans between September 2019 and December 2021 were retrospectively included. Using the syngo.via post-processing workstation, the data were applied to generate three-dimensional (3D) and virtual bronchoscopy (VB) simulations of a bronchial tree. The reconstructed images were then interpreted to identify and categorize distinct bronchial patterns in the left superior and lingular lobes. Cross-tabulation analysis and the Pearson Chi-square (χ2) test were used to calculate the constituent ratios of bronchial branch types and determine their significance between male and female groups. RESULTS: Our results revealed mainly four distinct types for the left superior lobe (LSL) bronchial tree, i.e., (B1 + 2, B3, 76.13%); (B1 + 2 + 3, 17.32%); (B1 + 3, B2, 5.74%); (B1a + B3, B1b + B2, 0.81%) and two types for the left lingular lobe (LLL) bronchial tree, i.e., (B4, B5, 91.05%); (B4, B5, B*, 8.95%). There were no significant sex-related differences in the proportion of bronchial branches in LLL (P > 0.05). However, sex-related differences were significant in the proportion of bronchial branches in LSL (P < 0.05). CONCLUSION: The current study has validated the presence of segmental bronchial variations in the left superior and lingular lobes. These findings may have a crucial effect on the diagnosis of symptomatic patients, as well as in carrying out procedures such as lung resections, endotracheal intubation, and bronchoscopies.
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Plants experiencing abiotic stress react by generating reactive oxygen species (ROS), compounds that, if allowed to accumulate to excess, repress plant growth and development. Anthocyanins induced by abiotic stress are strong antioxidants that neutralize ROS, whereas their over-accumulation retards plant growth. Although the mechanism of anthocyanin synthesis has been revealed, how plants balance anthocyanin synthesis under abiotic stress to maintain ROS homeostasis is unknown. Here, ROS-related proteins, SIMILAR TO RCD-ONEs (SROs), were analysed in Zea mays (maize), and all six SRO1 genes were inducible by a variety of abiotic stress agents. The constitutive expression of one of these genes, ZmSRO1e, in maize as well as in Arabidopsis thaliana increased the sensitivity of the plant to abiotic stress, but repressed anthocyanin biosynthesis and ROS scavenging activity. Loss-of-function mutation of ZmSRO1e enhanced ROS tolerance and anthocyanin accumulation. We showed that ZmSRO1e competed with ZmR1 (a core basic helix-loop-helix subunit of the MYB-bHLH-WD40 transcriptional activation complex) for binding with ZmPL1 (a core MYB subunit of the complex). Thus, during the constitutive expression of ZmSRO1e, the formation of the complex was compromised, leading to the repression of genes, such as ZmA4 (encoding dihydroflavonol reductase), associated with anthocyanin synthesis. Overall, the results have revealed a mechanism that allows the products of maize SRO1e to participate in the abiotic stress response.
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Antocianinas/biossíntese , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Zea mays/fisiologia , Antocianinas/fisiologia , Arabidopsis , Regulação da Expressão Gênica de Plantas , Estresse Oxidativo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Zea mays/genética , Zea mays/metabolismoRESUMO
Initially discovered in yeast, mitochondrial retrograde signalling has long been recognised as an essential in the perception of stress by eukaryotes. However, how to maintain the optimal amplitude and duration of its activation under natural stress conditions remains elusive in plants. Here, we show that TaSRO1, a major contributor to the agronomic performance of bread wheat plants exposed to salinity stress, interacted with a transmembrane domain-containing NAC transcription factor TaSIP1, which could translocate from the endoplasmic reticulum (ER) into the nucleus and activate some mitochondrial dysfunction stimulon (MDS) genes. Overexpression of TaSIP1 and TaSIP1-∆C (a form lacking the transmembrane domain) in wheat both compromised the plants' tolerance of salinity stress, highlighting the importance of precise regulation of this signal cascade during salinity stress. The interaction of TaSRO1/TaSIP1, in the cytoplasm, arrested more TaSIP1 on the membrane of ER, and in the nucleus, attenuated the trans-activation activity of TaSIP1, therefore reducing the TaSIP1-mediated activation of MDS genes. Moreover, the overexpression of TaSRO1 rescued the inferior phenotype induced by TaSIP1 overexpression. Our study provides an orchestrating mechanism executed by the TaSRO1-TaSIP1 module that balances the growth and stress response via fine tuning the level of mitochondria retrograde signalling.
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Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Salinidade , Tolerância ao Sal/genética , Fatores de Transcrição/metabolismo , Triticum/metabolismoRESUMO
Saline-alkali soil is a major environmental problem affecting crop productivity. One of the most effective approaches to combat it is to breed stress-tolerant plants through genetic engineering. Shanrong No. 4 (SR4) is an alkaline-tolerant cultivar of bread wheat (Triticum aestivum) derived from asymmetric somatic hybridization between the common wheat cultivar Jinan 177 (JN177) and tall wheatgrass. In this study, we aimed to explore the structure and function of alkalinity stress-responsive long non-coding RNAs (lncRNAs) in wheat. Sequencing was employed to identify the lncRNAs associated with stress tolerance and their corresponding targets. Approximately 19 000 novel lncRNA sequences were detected in SR4 and JN177. Upon exposure to alkaline stress, SR4 differentially expressed 5691 lncRNAs, whilst JN177 differentially expressed 5932. We selected five of them (L0760, L6247, L0208, L2098, and L3065) and generated seedlings of transiently knocked down strains using the virus-induced gene-silencing method. Knockdown of L0760 and L2098 caused the plants to exhibit sensitivity to alkaline stress, whereas knockdown of L6247, L0208, and L3065 increased the ability of plants to tolerate alkaline stress. We constructed lncRNA-miRNA-target-mRNA networks and alkali-response-related lncRNA-target-mRNA association networks to analyse the functions of lncRNAs. Collectively, our results demonstrate that lncRNAs may perform different roles under alkaline stress conditions.
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MicroRNAs , RNA Longo não Codificante , Álcalis , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , MicroRNAs/genética , Melhoramento Vegetal , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Triticum/genéticaRESUMO
Gaseous reactive nitrogen (Nr) emissions from agricultural soils to the atmosphere constitute an integral part of global N cycle, directly or indirectly causing climate change impacts. The extensive use of N fertilizer in crop production will compromise our efforts to reduce agricultural Nr emissions in China. A national inventory of fertilizer N-induced gaseous Nr emissions from croplands in China remains to be developed to reveal its role in shaping climate change. Here we present a data-driven estimate of fertilizer N-induced soil Nr emissions based on regional and crop-specific emission factors (EFs) compiled from 379 manipulative studies. In China, agricultural soil Nr emissions from the use of synthetic N fertilizer and manure in 2018 are estimated to be 3.81 and 0.73 Tg N yr-1 , with a combined contribution of 23%, 20% and 15% to the global agricultural emission total of ammonia (NH3 ), nitrous oxide (N2 O) and nitric oxide (NO), respectively. Over the past three decades, NH3 volatilization from croplands has experienced a shift from a rapid increase to a decline trend, whereas N2 O and NO emissions always maintain a strong growth momentum due to a robust and continuous rise of EFs. Regionally, croplands in Central south (1.51 Tg N yr-1 ) and East (0.99 Tg N yr-1 ) of China exhibit as hotspots of soil Nr emissions. In terms of crop-specific emissions, rice, maize and vegetable show as three leading Nr emitters, together accounting for 61% of synthetic N fertilizer-induced Nr emissions from croplands. The global warming effect derived from cropland N2 O emissions in China was found to dominate over the local cooling effects of NH3 and NO emissions. Our established regional and crop-specific EFs for gaseous Nr forms provide a new benchmark for constraining the IPCC Tier 1 default EF values. The spatio-temporal insight into soil Nr emission data from N fertilizer application in our estimate is expected to advance our efforts towards more accurate global or regional cropland Nr emission inventories and effective mitigation strategies.